1. Field of the Invention
This invention relates generally to a connector, and more particularly to a connector having a base member provided with contacts and a cover member likewise provided with contacts, the contacts on the base member and cover member being capable of contacting mutually different leads arranged on an electric part, wherein both the contacts on the base member and cover member can be contacted with the leads in a positive manner.
2. Prior Art
There has been known a connector having a contact structure for contacting IC contacts from opposite sides, having a base member constituting a connector body, and a cover member, the cover member being closed onto the base member after an IC is placed on the latter, so that contact relation can be maintained while holding the IC, wherein contacts are separately arranged on the base member and cover member in order to cope with a known requirement for a very small pitch arrangement of the leads of an IC, thereby enabling the contacts on both the base member and cover member to be alternately contacted with upper surfaces and under surfaces of the leads when the cover member is closed onto the base member.
In the above connector, the contacts on both the base member and cover member are provided with elasticity in order to obtain contact pressure against the leads.
By virtue of the arrangement that the contacts are alternately arranged on the base member and cover member, the above connector has the advantages that while the contact pitches on both the base member and cover member are large, the requirement for a very small pitch arrangement of the leads is satisfied. However, this conventional connector has the problem that the leads tend to be deformed. This problem will be described with reference to a conceptual view shown in FIG. 11. When the cover member 2 is closed on the base member 1, the leads 5 are urged against the elastic contacts 3 on the base member 1 by the cover member 2. Then, the leads 5 are flexed downwardly while compressing the contacts 3. On the other hand, the leads 6, which are urged against the elastic contacts 4 on the cover member 2, are flexed upwardly while compressing the contacts 4. Since reverse bending forces are applied to the leads 5, 6, the leads 5, 6 are subjected to a thermal test, etc. in that state. As a result, the leads 5, 6 are incapable of returning to their original states even after the pressure is removed. This means that the leads 5, 6 suffer from so-called "permanent deformation", which also causes vertical irregular arrangement of the leads, thus jeopardizing flatness. In recent years, leads of IC, etc. have been formed smaller and smaller, and they are becoming more and more fragile. Therefore, it is indispensable to obviate the above-mentioned problems.